Support and Movement Bone Tissue and also the Skeletal device Bone Tissue and the Skeletal system introduction

Figure 6.1 Child Looking in ~ Bones Bone is a living tissue. Unlike the skeleton of a fossil make inert by a process of mineralization, a child’s bones will continue to grow and develop when contributing to the support and duty of other body systems. (credit: James Emery)


After examining this chapter, you will certainly be maybe to: 

List and also describe the functions of bonesDescribe the classes of bonesDiscuss the procedure of bone formation and developmentExplain exactly how bone repairs itself after a fractureDiscuss the result of exercise, nutrition, and also hormones on bone tissueDescribe just how an imbalance of calcium can influence bone tissue

Bones make good fossils. If the soft organization of a as soon as living organism will decay and fall away end time, bone organization will, under the ideal conditions, undergo a process of mineralization, effectively transforming the bone come stone. A well-preserved fossil skeleton can provide us a an excellent sense of the size and also shape of one organism, just as your skeleton help to define your size and also shape. Uneven a fossil skeleton, however, your skeleton is a framework of living tissue that grows, repairs, and renews itself. The bones within it are dynamic and facility organs that offer a variety of important functions, including some important to keep homeostasis.

You are watching: Bone tissue is dissolved and returned to the circulation in the process of

through the end of this section, you will be able to:Define bone, cartilage, and also the bones systemList and also describe the features of the skeletal system

Bone, or osseous tissue, is a hard, dense connective organization that forms most of the adult skeleton, the support structure of the body. In the areas of the skeleton wherein bones relocate (for example, the ribcage and joints), cartilage, a semi-rigid type of connective tissue, offers flexibility and also smooth surfaces for movement. The skeletal system is the body mechanism composed of bones and also cartilage and also performs the following crucial functions for the human body:

supports the bodyfacilitates movementprotects interior organsproduces blood cellsstores and also releases minerals and fat

Support, Movement, and also Protection

The most noticeable functions that the skeletal system are the gun functions—those visible by observation. Just by looking in ~ a person, you deserve to see exactly how the skeleton support, facilitate movement, and also protect the person body.

Just as the steel beams that a building carry out a scaffold to assistance its weight, the bones and cartilage of her skeletal mechanism compose the scaffold the supports the rest of your body. Without the skeletal system, you would certainly be a limp fixed of organs, muscle, and also skin.

Bones additionally facilitate motion by serving together points of attachment for your muscles. While part bones only serve as a assistance for the muscles, others likewise transmit the forces produced when your muscles contract. Native a mechanical point of view, bones act as levers and joints offer as fulcrums (Figure 6.2). Uneven a muscle spans a joint and also contracts, a bone is not going come move. For information on the interaction of the skeletal and muscular systems, the is, the musculoskeletal system, seek added content.


Figure 6.2 Bones assistance Movement Bones act as levers when muscles expectations a joint and also contract. (credit: Benjamin J. DeLong)

Bones additionally protect inner organs native injury by extending or surrounding them. Because that example, her ribs defend your lungs and also heart, the skeleton of your vertebral shaft (spine) protect your spinal cord, and also the skeleton of your cranium (skull) protect your brain (Figure 6.3).


Figure 6.3 Bones safeguard Brain The cranium completely surrounds and protects the brain from non-traumatic injury.



An orthopedist is a doctor who specializes in diagnosing and treating disorders and injuries related to the musculoskeletal system. Some orthopedic problems can be treated with medications, exercises, braces, and also other devices, however others might be best treated with surgical procedure (Figure 6.4).


Figure 6.4 Arm Brace An orthopedist will occasionally prescribe the use of a brace that reinforces the underlying bone framework it is being supplied to support. (credit: Juhan Sonin)

While the origin of the word “orthopedics” (ortho- = “straight”; paed- = “child”), literally way “straightening of the child,” orthopedists can have patient who selection from pediatric come geriatric. In current years, orthopedists have also performed prenatal surgery to correct spina bifida, a congenital defect in which the neural canal in the spine of the fetus fails to close totally during embryologic development.

Orthopedists commonly treat bone and joint injuries however they additionally treat various other bone conditions including curvature the the spine. Lateral curvatures (scoliosis) deserve to be severe enough to on slide under the shoulder tongue (scapula) forcing the up together a hump. Spinal curvatures can likewise be extreme dorsoventrally (kyphosis) resulting in a hunch ago and thoracic compression. These curvatures often appear in preteens together the an outcome of poor posture, abnormal growth, or indeterminate causes. Mostly, castle are conveniently treated by orthopedists. As human being age, accumulated spinal shaft injuries and diseases choose osteoporosis can additionally lead come curvatures the the spine, therefore the stooping you periodically see in the elderly.

Some orthopedists sub-specialize in sports medicine, i beg your pardon addresses both basic injuries, such as a sprained ankle, and facility injuries, such as a take it rotator cuff in the shoulder. Treatment can variety from practice to surgery.

Mineral Storage, power Storage, and Hematopoiesis

On a metabolic level, bone organization performs several an important functions. Because that one, the bone procession acts as a reservoir because that a variety of minerals essential to the functioning of the body, particularly calcium, and also phosphorus. This minerals, integrated into bone tissue, can be released earlier into the bloodstream to maintain levels necessary to support physiological processes. Calcium ions, because that example, are necessary for muscle contractions and controlling the circulation of various other ions connected in the transmission of nerve impulses.

See more: How Much Anchovy Paste Equals 4 Anchovies, Access To This Page Has Been Denied

Bone likewise serves together a site for fat storage and blood cabinet production. The softer connective tissue that fills the inner of most bone is described as bone marrow (Figure 6.5). There room two species of bone marrow: yellow marrow and also red marrow. Yellow marrow contains adipose tissue; the triglycerides stored in the adipocytes of the tissue deserve to serve as a resource of energy. Red marrow is where hematopoiesis—the manufacturing of blood cells—takes place. Red blood cells, white blood cells, and platelets space all created in the red marrow.


Figure 6.5 Head of Femur showing Red and Yellow Marrow The head that the femur has both yellow and red marrow. Yellow marrow stores fat. Red marrow is responsible for hematopoiesis. (credit: modification of job-related by “stevenfruitsmaak”/Wikimedia Commons)